It is often necessary to ship materials in a steady routine back and forth from one address to another. In such service, it would be very helpful to have a permanent lockable box and address plate, which can easily be changed to facilitate shipment in both directions. Such a box would be particularly convenient for shipping sets of artificial teeth back and forth from a dentist to a supplier to permit the supplier to replenish the set when substantially depleted. An object of this invention is, therefore, to provide a relatively simple and economical lockable box having a reversible address plate for shipping articles back and forth between two addresses.